Scientists invent artificial neurons that ‘talk’ to real brain cells, paving way to better brain implants
Engineers have printed tiny artificial neurons that can “talk” with mouse brain cells, and the development could pave the way for innovations in computing and medicine.
The work, published on April 15 in the journal Nature Nanotechnologyadds to a growing field that aims to build computers that mimic the inner workings of the brain.
“We are trying to mimic the brain as closely as possible,” said the study co-author. Marc Hersamprofessor of materials science and engineering at Northwestern University. “What motivates us is to find an alternative to conventional digital computing to process large amounts of data in a more energy-efficient way,” he told Live Science.
This work could also pave the way for new brain-computer interfaces, which would allow electronic devices to be controlled using brain activity. Brain-computer interfaces can be used to control prosthetic limbs or assistive communication devicesFor example.
Because neuromorphic computers are designed to mimic the brain, they should be well suited to interact with brain tissue. Additionally, some scientists have suggested that artificial neurons could replace damaged nerve cells or restore brain function lost in degenerative diseases such as Alzheimer’s disease.
Bottle the brain in a chip
To recapitulate brain tissue, you can’t use traditional silicon chips that are rigid and made of repeating transistors arranged in two-dimensional structures. They have fixed connections that cannot evolve.
We are far from the delicate infrastructure of the brain. Brain cells are physically flexible, vary depending on their location, and communicate in a 3D matrix that changes over time. Connections between neurons can become stronger if used consistentlyor they can fade if underutilized. All of these properties are necessary to create the complex processors that constantly make sense of the complex world around us.
Because of these discrepancies between the brain and the machinery, most brain-computer interfaces fail to integrate seamlessly into the brain; instead, they rely on relatively crude impulses to communicate with neurons. Making effective artificial neurons means finding materials that feel and act like neurons, in the sense that they mimic neuronal firing patterns and adjust those signals as needed.
Artificial neurons designed before the new study tend to use either soft organic materials, such as gels or fabrics that can transmit electrical and chemical signals, or hard metal oxides. Each approach has drawbacks: While tip patterns in soft materials tend to be too slow, those in hard materials tend to be too fast, Hersam explained.
To better replicate neurons, Hersam and his team used printable inks containing tiny flakes of molybdenum disulfide, an inorganic compound that acts as a semiconductor, and graphene, an electrical conductor. The inks are printed on a flexible polymer substrate.
We can get all different types of cutting-edge responses that mimic biology.
Mark Hersam, professor of materials science and engineering at Northwestern University
Historically, these substrates have been considered an obstacle because the polymers interfere with electrical currents. But as Hersam and his colleagues discovered, this can be a boon for artificial neurons, as the team discovered that the polymers can be manipulated to control how electricity flows through the lab-made brain cell.
“The key innovation was this partial decomposition of the polymer,” Hersam said.
By carefully tailoring the way the polymer heats and breaks down, engineers can create tiny filaments of energy. Rather than rising steadily, the current flowing through the neuron rises and then falls, allowing a sudden release of energy similar to a neuronal spike. This action is called “negative differential pull-up resistance”.
And by adjusting the device settings, the team was able to generate more complex signaling patterns, including a series of spikes spaced over time or sudden bursts of spikes. “We can get all different types of cutting-edge responses that mimic biology,” Hersam said.
To prove it, the scientists placed their artificial neurons next to slices of mouse brains in a laboratory dish. They found that the mouse neurons fired at the same rate as the artificial neurons, suggesting that the tissue could decode the artificial signal as if it had arisen from real tissue.
Artificial neurons of the future
Timothy Leviprofessor of bioelectronics who works on artificial neurons at the University of Bordeaux in France, praised the new type of artificial neuron, noting that it can “adapt to the normal frequency of neurons,” he said.
Levi, who was not involved in the research, said the work adds to a series of recent studies showing that artificial neurons can communicate with biological neurons. These developments have been accompanied by a series of advances improving the way artificial neurons are built, how they connect to each other and how they are programmed, Levi said.
He stressed, however, that artificial neurons are still far from communicating fully and meaningfully with biological neurons. “We can control them for a short time, but not yet for a long time,” he said. They are therefore not yet suitable as permanent additions to the human brain, for example.
Much work remains to be done to understand how the brain works so that it can be faithfully reproduced by a computer, Levi and Hersam noted. Furthermore, artificial neurons are not enough: they must be connected together at the level of artificial synapses.
“The border problem,” Hersam said, “is that we have a series of devices that mimic different elements of the brain, but we have to integrate them together into circuits that achieve all the functionality.”
Hadke, SS, Klingler, CN, Brown, ST et al. MoS printed2 memristive nanosheet arrays to power neurons with multi-order complexity. Natural nanotechnology. (2026). https://doi.org/10.1038/s41565-026-02149-6
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